JP5643286B2 - Contact clamping device for thin silicon rods - Google Patents

Description

  The present invention relates to a contact-type clamping device for incorporating a fine silicon rod into an electrical contact with a silicon rod in a silicon vapor deposition reactor, and a rod holder generally made of graphite for supporting each end of the fine silicon rod. It is related with the contact-type clamp apparatus provided with.

  In semiconductor technology and photovoltaic technology, it is known to produce high purity silicon rods, for example by the Siemens method in a vapor deposition reactor, in particular in a chemical vapor deposition reactor. For this method, a fine silicon rod is first placed in a reactor, after which silicon is deposited on the silicon rod during the deposition reaction. Usually, the thin silicon rod is supported by a contact-type clamping device, and the silicon rod is supported in a desired direction by one hand and the electrical contact is supplied by the other hand. During the deposition process, electrical contact is required to heat the silicon rod by resistance heating to a temperature at which a predetermined voltage is applied and vapor or gaseous silicon is deposited on the thin silicon rod. The deposition temperature is 900 to 1340 ° C, and generally 1100 to 1200 ° C. If this deposition temperature exceeds the upper limit value, there is a risk that the fine silicon rod will be broken or melted, so it should not exceed the upper limit value.

  If the silicon rod breaks or melts, the deposition must generally be stopped, and the silicon deposition reactor must be cooled sufficiently to replace the damaged thin silicon rod with a new one before the silicon deposition reaction. You must open the bowl. For this purpose, it is necessary to cool the silicon deposition reactor first, and the gas must be exchanged before the reactor is opened, which requires a considerable amount of time, which greatly reduces productivity. Furthermore, loss of raw materials also occurs.

  German publication DE 1187098A describes a silicon rod manufacturing apparatus and method of the type described above. The apparatus used to carry out the method described there comprises a reaction vessel mainly made of glass or quartz, in which two fine silicon rods are self-supporting, made of pure carbon or Supported by a graphite rod holder. At each free end of the top of the fine silicon rod, the silicon rod is made of silicon or pure carbon to form a current circuit through each rod holder, fine silicon rod and bridge, and to further promote the resistance heating described above. Connected to each other via a sex bridge.

  The reaction vessel is surrounded by a reflector cylinder or by a heating resistor. Once the fine silicon rod is incorporated into the reaction vessel, the silicon rod is heated to the deposition temperature by the resistance heating described above, and by any additional heating elements. After reaching the deposition temperature, a mixture of a silicon-containing gas such as silicon tetrachloride or trichlorosilane and another gas such as hydrogen is introduced into the reaction vessel. Alternatively, monosilane or silicon iodide can be used as the silicon-containing gas.

  In the latest equipment for coating fine silicon rods, two or more fine silicon rods are arranged adjacent to each other and coated simultaneously. In this case, adjacent thin silicon rods are always connected to each other by a conductive bridge, and are connected to a current source by a rod holder at the base.

  When the fine silicon rod is electrically heated using resistance heating, care must be taken not to exceed a predetermined temperature. In particular, care must be taken during the first hours of heating the fine silicon rod to the deposition temperature and entering the deposition process. However, problems still arise with the rod holder.

  The rod holder is usually made of graphite, has a conical tapered shape, and may have a support space with a blind hole into which a thin silicon rod is inserted from above. Thereby, the rod holder and the fine silicon rod are taper-connected. The inserted thin silicon rod usually has a circular or rectangular cross section having a diameter of 6 to 10 mm. The tapered portion of the support space must be manufactured with great precision so as to provide sufficient mechanical and electrical contact between the rod holder and the fine silicon rod, resulting in high manufacturing costs.

  The rod holder may be provided with a slit in the area of the blind hole so as to compensate for some durability when heated and to reduce mechanical stress.

  In particular, the electrical contact of the silicon rod with the rod holder is important. If the fine silicon rod has a rectangular cross section, an electromechanical contact is made along the edge of the silicon rod. And the contact surface becomes extremely narrow, and damage is easily caused by mechanical strain on the edge. Furthermore, the electrical contact resistance increases along the edge. However, for fine silicon rods with a circular cross section, electromechanical contact is made along a circumferential line along the entire circumference of the fine silicon rod.

  Particularly in the early stages of the heating process, a contact heating zone occurs at the point of contact between graphite and silicon, and mechanical stress can melt or damage the fine silicon rod. This causes the above-mentioned unfavorable results, i.e. the heating process must be interrupted and the silicon deposition reactor must be newly adapted to complex procedures.

  In particular, when the contact heating area becomes wide, that is, when it exceeds about 1/4 of the diameter of the rod or when contact heating is found over the entire circumference of the thin silicon rod having a circular cross section, the fine silicon rod is damaged. .

  The problem to be solved by the present invention is to provide a contact clamping device for a fine silicon rod that overcomes the above-mentioned problems.

  The problem to be solved by the present invention is solved by a contact-type clamping device according to claim 1. Furthermore, embodiments of the invention are derived from the dependent claims.

  The contact-type clamping device is a device that incorporates a fine silicon rod and makes electrical contact with the silicon rod, particularly in a silicon vapor deposition reactor, and includes a rod holder that supports one end of the fine silicon rod. Comprising at least three contact elements arranged around a support space supporting the rod, each contact element forming a contact surface facing the support space in an electromechanical contact with the fine silicon rod; The contact surfaces of adjacent contact elements are spaced apart.

  As a result, a predetermined number of electromechanical contact surfaces can be formed on the rod holder that holds the fine silicon rod, and the electromechanical contact surface matches the shape of the fine silicon rod. The distance between the contact surfaces prevents possible “travelling” of the contact heating area, reducing the risk of the fine silicon rods melting and being damaged.

  Compared to using a conventional tapered connection, a much larger current can be passed through the formed contact surface, allowing higher temperatures to be reached, especially for thin silicon rods faster. The temperature can be raised. Furthermore, since the cross-sectional area of graphite is reduced, the graphite material becomes hotter and a strong mechanical resistance connection between graphite and silicon can be realized.

  The contact surface extends parallel to the longitudinal axis of the rod holder coinciding with the longitudinal axis of the fine silicon rod, and is preferably in contact over a substantial area of the silicon rod. Therefore, the contact surface is striped, and can be made to coincide with the outer shape of the fine silicon rod. Here, the striped contact surface is essentially a contact surface having a width narrower than the periphery of the fine silicon rod, and having a width such that the total width of all the contact surfaces is smaller than the periphery of the fine silicon rod. Should be understood. The sum of the widths of all contact surfaces is less than or equal to about half the circumference of the fine silicon rod.

  In one embodiment of the invention, the contact elements are movable relative to one another, in particular to the support space side. As a result, one end of the thin silicon rod is first freely inserted into the support space, and then the contact elements are moved relative to each other to fix the one end of the fine silicon rod by the contact surface in the support space. Can be tightened. as a result. A good mechanical and electrical contact of the fine silicon rod can be achieved in the support space.

In one embodiment of the invention, the contact element is in close contact and / or a pressure fit with the fine silicon rod at the lower end of the fine silicon rod.
In another embodiment of the invention, the contact element is in contact with the fine silicon rod with a pressure fit at the lower end.

  The rod holder has the advantage that it is designed in two parts consisting of a base element and a clamping element with a contact element. While the base element can be reused, the clamping element should be seen as a consumable element and a new clamping element should be used for each new fine silicon rod. This is due to the fact that the silicon rod grows to the clamp element as the silicon rod continually thickens during the silicon growth process, so that the clamp element is damaged by a strong bond with silicon. The clamping element is closely fitted with the base element and joined to the base element by a slight pressure fit to allow easy replacement. Of course, the rod holder may also be composed of multiple components, that is, it may be composed of two or more components.

  In one embodiment, the base element comprises a tapered cradle, in particular a conically tapered cradle. The clamp element has a tapered outer shape corresponding to the cradle. This design makes it possible, on the one hand, to automatically center each element on the other hand, and on the other hand to facilitate clamping elements when inserting or removing the clamping element from the recess. Can be handled. The taper of the cradle of the base element and the tapered outer shape of the clamp element are preferably sized such that when the clamp element moves to the cradle side, the contact elements move together to narrow the support space. The movement of the contact elements is preferably perpendicular to the contact surface of the contact elements. Thereby, when the clamp element is inserted into the cradle, the fine silicon rod received in the support space can be automatically clamped (tightened). As a result, a wedge effect with a high contact pressure occurs and the contact resistance between the contact element and the fine silicon rod can be reduced.

  By tightening (clamping) over a substantial area, the mechanical strain is reduced, and the risk of the fine silicon rod falling can be reduced. First, the clamping element can be gently inserted into the cradle. As a result, the support space has not yet narrowed. Then, in order to easily introduce the fine silicon rod into the support space and tighten (clamp) the fine silicon rod, it is only necessary to finally push it deeply into the cradle. Here, in particular, in order to tighten (clamp), it is not necessary to add other elements in addition to the clamp element and the base element, and there is an advantage that the apparatus configuration is simplified. Furthermore, each element part inserted into the vapor deposition reactor is reduced, and heating of the vapor deposition temperature is promoted. Additional elements can cause contamination or become contaminated to the extent that they must be periodically replaced and / or cleaned in the deposition process.

  In order to obtain a stable and clear clamping (clamp), it is advantageous for the contact element to move perpendicular to the contact surface. This can be achieved by designing the clamping element and / or the cradle to correspond. In order to achieve a stable and clear clamping (clamp), the contact surface of the contact element can also be brought into contact with the fine silicon rod over a substantial area, matching the contour of the fine silicon rod. For example, a contact surface for a round thin silicon rod exhibits a curved surface corresponding to the curvature of the thin rod, while a contact surface for a square thin rod indicates a contact surface extending over a substantial area.

  In one embodiment, the contact elements are equally spaced around the support space in order to achieve a symmetrical contact of the fine silicon rods. In a first example for a fine silicon rod with a rectangular cross-sectional area, the clamping element consists of four thin contact elements with narrow contact surfaces distributed, for example, every 90 °. In a second example, the clamping elements for a fine silicon rod with a circular cross-sectional area are distributed, for example, every 120 ° with respect to each other, and three thin with a narrow contact surface with a curvature corresponding to the curvature of the fine silicon rod. It consists of contact elements.

  In one particular embodiment, the contact elements are separate elements that are connected to each other by a coupling element at least before being inserted. This separate element has the flexibility advantageous for clamping (clamping), while the connecting element allows the contact element to be handled as a unit before using the contact element. The connecting element between the contact elements is flexible and / or has a predetermined cut point so that it can move relatively between the contact elements. The contact element and the connecting element are integrally formed from a graphite material, for example by machining.

  According to one embodiment, a clamp ring attached to the base element is provided, the cradle receiving the contact element is formed between the clamp ring and the base element, and when the clamp ring is attached to the base element, the contact element is The cradle is formed in such a dimension that it can move relative to each other and in particular to the support space side. Such a clamp ring can improve the stability of the contact element in the base body as required, and can increase the force for clamping (clamping) the fine silicon rod. The clamp ring can be attached to the base element, for example by screwing, or it can be fastened to the base element by a quick-release mechanism. Here, the clamping ring has an opening with a tapered inner wall, for example adapted to the tapered outer shape of the contact element, in order to ensure the movement of the contact element. The clamp ring need not be electrically conductive, but should be composed of a sufficiently strong and heat resistant material.

  The contact-type clamping device according to the present invention can have a positive influence on the process control in the silicon deposition reactor. This is because silane vapor or gas is already supplied at the beginning of the heating process of the fine silicon rod. As a result of the deposition of the supplied silane in the higher temperature region, high temperatures can be achieved via the contact surface, especially in the region of the contact surface, from the beginning of the heating process. This leads to a self-healing action if there is slight damage to the fine silicon rod in this region.

FIG. 1 is a plan view of a rod holder into which a thin silicon rod having a rectangular cross-sectional area is inserted. FIG. 2 is a side view of the rod holder shown in FIG. FIG. 3 is a side view of the rod holder shown in FIG. 2 when a thin silicon rod is inserted. FIG. 4 is a cross-sectional view taken along line IV-IV of the rod holder shown in FIG. 1 when the fine silicon rod is removed. FIG. 5 is a plan view showing another rod holder designed as a drill chuck type into which a thin silicon rod having a circular cross-sectional area is inserted. 6 is a cross-sectional view of the rod holder shown in FIG. 5 taken along the line VI-VI. FIG. 7 is a plan view showing still another rod holder. 8 is a cross-sectional view of the rod holder shown in FIG. 7 taken along line VIII-VIII.

In the following, the invention is described in more detail by means of various embodiments with reference to the drawings.
The terms “upper (top)”, “lower (bottom)”, “right” and “left” used here correspond to the expressions in the drawing and indicate preferred positions and directions. However, the present invention is not limited by these terms.
FIG. 1 is a plan view of a rod holder 1 according to the first embodiment. The rod holder 1 is made of graphite, for example, and is shown with a thin silicon rod 2 having a rectangular cross-sectional area inserted. 2 and 3 show side views of the rod holder 1 shown in FIG. 1, respectively. FIG. 2 shows the rod holder when the thin silicon rod 2 is not inserted, and FIG. 3 shows the thin silicon rod 2. The rod holder when the is inserted is shown. FIG. 4 is a cross-sectional view of the rod holder shown in FIG. 1 taken along the line IV-IV, and a simplified silicon rod is omitted.

Such a rod holder 1 makes electrical contact with the fine silicon rod as described above, generates a thicker silicon rod during the deposition process, and basically holds the fine silicon rod in a self-supporting state. For purposes, it is used in a silicon deposition reactor (not shown). Basically, it is understood that one end of the fine silicon rod is received and held by the rod holder, while the majority of the fine silicon rod protrudes from the rod holder and is exposed to the process gas atmosphere. Should be.
The rod holders are paired so as to form an electrical circuit via the rod holder, the fine silicon rod received in the rod holder, and the corresponding conductive connection at the corresponding free end of the fine silicon rod 2. Has been placed. As described above, in order to heat the fine silicon rod 2 to the deposition temperature, this electric circuit enables resistance heating of the fine silicon rod 2 in conjunction with the electric supply.

  As shown in FIG. 4, the rod holder comprises a base element 7 and a clamping element 8 each designed as a separate element. The clamping element 8 is used to receive a fine silicon rod and make electrical contact with the fine silicon rod, and is used disposable to contact the fine silicon rod during the deposition process. The base element 7 is used to receive the clamping element 8 and to fix the clamping element 8 and is used multiple times during the deposition process due to the distance from the fine silicon rod 2.

  The base element basically has a cylindrical shape, and the upper end is formed in a conical shape. The conical upper end has a recess, and the recess tapers downward toward the base. The recess extends into the cylindrical portion of the base element.

  The clamping element 8 comprises a lower base 3 and four contact elements 4.1, 4.2, 4.3, 4.4 extending upward from the lower base. The lower surface of the base part 3 is formed corresponding to the recess of the base element 7 so as to fit closely. The upper surface is formed in a planar shape. Due to the tapered shape of the recess and the corresponding shape of the base 3, each element is automatically centered when the clamping element 8 is inserted into the base element. The base 3 has a flat upper surface and has a portion inclined in contact with the upper surface. The inclination of the inclined portion coincides with the inclination of the tapered portion of the base element 7.

  Contact elements 4.1, 4.2, 4.3, and 4.4 extend from the top surface of base 3, and each contact element is typically in the form of a right triangle when viewed from the side (FIG. 4). ). The contact elements are arranged so that one side sandwiching a right angle is parallel to the upper surface of the base 3 and the other side is vertical. The contact elements 4.1, 4.2, 4.3, 4.4 are oriented radially in the direction of the center of the surface and are located at a distance so as to form a support space between the elements. . The contact elements 4.1, 4.2, 4.3, 4.4 are arranged at an equal angle of 90 ° to each other, and each side of the contact element perpendicular to the upper surface of the base is inside the support space. It is arranged to be located. Each of the hypotenuses of the contact elements 4.1, 4.2, 4.3, 4.4 is inclined outwardly, which is the same as the taper of the base element 7 . The triangular free upper end is truncated at the tip as shown in FIG. 4 to avoid easily damaging the contact element or damaging the fine silicon rod 2 at this point. .

  The contact elements 4.1, 4.2, 4.3, and 4.4 form a striped contact surface along an inner peripheral surface that extends parallel to the longitudinal axis A of the rod holder. As clearly shown in FIGS. 1 to 3, the contact surface is in contact with the fine silicon rod at the center of each edge face width along the edge face of the fine silicon rod having a rectangular cross-sectional area that is received in the support space. To do. It is preferable that the width of each contact surface corresponds to 50% of the edge surface width of the fine silicon rod 2 at the maximum.

  FIG. 5 is a plan view showing another rod holder 6 designed as a drill chuck type having a receiving portion for receiving the thin silicon rod 3 having a circular cross-sectional area. 6 is a cross-sectional view taken along line VI-VI of the rod holder 6 shown in FIG. The rod holder 6 and the fine silicon rod 3 are inserted into the receiving portion in the same manner as described above.

As clearly shown in FIG. 6, the rod holder 6 comprises a base element 7 corresponding to the aforementioned base element and a clamp element 8 corresponding to the aforementioned clamp element. The clamping element 8 is a part of a clamping device (not shown) provided with a clamping ring 9 in addition to the clamping element 8. The clamping element 8 is used to make electromechanical contact with the fine silicon rod 3 and is used disposable to contact the fine silicon rod during the deposition process. The base element 7 is used to receive the clamping element 8 and to fix the clamping element 8 and is used several times during the deposition process due to the distance from the fine silicon rod 2. The clamp ring 9 is used to clamp the clamping element 8 against the base element as described below. In addition, the clamp ring 9 is used a plurality of times during the vapor deposition process because there is a distance from the thin silicon rod 2.
The base element 7 is basically cylindrical and its upper surface is usually flat on which the clamping element 8 can be placed.

The clamping element comprises three contact elements 5.1, 5.2, 5.3, each contact element generally in the form of a right triangle when viewed from the side, similar to the contact elements described above. Each contact element 5.1,
5.2 and 5.3 are arranged such that one side across the right angle is parallel to the upper surface of the base element 7 and the other side is vertical. The contact elements 5.1, 5.2, 5.3 are oriented radially in the direction of the center of the surface and are located so as to form a support space between the elements. The contact elements 5.1, 5.2, 5.3 are arranged at an equal angle of 120 ° to each other such that each side of the contact element perpendicular to the upper surface of the base is located inside the support space Has been placed. Each of the hypotenuses of the contact elements 5.1, 5.2, and 5.3 forms an outward slope, which is the same as the slope of the taper portion of the base element 7. The three contact elements 5.1, 5.2, 5.3 thus form a cone-shaped contour. The triangular free upper end is again cut off at the apex, as shown in FIG.

The contact elements 5.1, 5.2, 5.3 form a striped contact surface along an inner peripheral surface extending parallel to the longitudinal axis A of the rod holder. The contact surface is rounded and conforms to the shape of the round thin silicon rod 3 so as to closely contact the thin silicon rod 3 received in the support space. The contact surface contacts up to 50% of the circumference of the fine silicon rod.
The contact elements 5.1, 5.2, 5.3 are separate elements that are able to move toward each other and are connected to each other by a coupling element at least before being inserted.

  The clamp ring 9 basically has a cup shape having a base portion having an opening 10 and a peripheral side portion perpendicular to the base portion. When used, the clamp ring 9 is turned upside down, that is, as shown in FIG. The side wall includes fixing means that are combined with the fixing means on the base body 7 along the inner peripheral surface in order to place the clamp ring 9 on the base body. Examples of fasteners are internal threads on the sidewalls and external threads on the base body, or corresponding elements for a simple removable or bayonet fastener. Other fasteners are of course possible.

  The opening 10 is formed such that the inner wall of the opening 10 having an inclination corresponding to the inclination of the contact elements 5.1, 5.2, 5.3 facing in the outward direction is in the center. As shown in FIG. 6, a part of the contact elements 5.1, 5.2, 5.3 is received between the clamp ring 9 and the base element 7 and the remaining part is the central opening of the clamp ring. 10 and extends outward. The inclined portion of the central opening is engaged with the inclined portion facing outward of the contact elements 5.1, 5.2, and 5.3. By such engagement, the contact elements 5.1, 5.2 and 5.3 can move so as to approach each other, and the support space for supporting the thin silicon rod 3 can be reduced, and the support The thin silicon rod 3 to be fixed can be fixed and clamped. In FIG. 6, a clamp ring 9 is incorporated on the contact element 5 and, like a drill chuck by movement in the axial direction and in the direction of the base element 7, the clamp ring 9 is at the lower end of a fine silicon rod 3 (not shown). The state of pressing the contact elements 5.1, 5.2, 5.3 around the part is shown. For this purpose, as shown in FIG. 6, the clamp ring 9 is joined to the base element 7 by screwing. Alternatively, the clamp ring 9 is clamped to the base element 7 by means using a simple attachment / detachment mechanism.

  In this embodiment, three contact elements with a clamp ring are shown, but instead four or more contact elements corresponding to the shape of the thin silicon rod to be inserted can be used. . Of course, it is also possible not to use a clamp ring with three or more than four contact elements shown.

  According to the present embodiment, the number of electromechanical contact surfaces between the rod holder 1 and the fine silicon rods 2 and 3 is 4 in the form of stripes in the longitudinal direction and in electrical mechanical contact with the fine silicon rods 2. The contact elements 4.1, 4.2, 4.3, 4.4 can be minimized by forming on the rod holder 1 (FIG. 1), or three contact elements 5.1 , 5.2, 5.3 can be minimized by forming them on the rod holder 6 (FIG. 4). The four contact elements 4 are arranged at an angle of 90 ° to each other, and the three contact elements 5.1, 5.2, 5.3 are arranged at an angle of 120 ° to each other.

The contact elements 4, 5 form a narrow contact surface and contact the fine silicon rods 2, 3 in a conformal manner at the lower end of the fine silicon rods as shown in FIGS. As shown in FIG. 5, they are in contact with each other by shape matching and pressure fitting.
The rod holder 1 can be designed as a two-piece type, it is composed of a base element 7 and a clamping element 8 as shown, or it can be designed as a single piece.

  In the present invention, on the one hand, a predetermined number of narrow electromechanical contact surfaces are formed between the thin silicon rods 2 and 3 and the rod holder 1, and on the other hand, the contact surfaces of the contact elements 4 and 5 and the fine silicon By increasing the distance between the rods 2 and 3, it is possible to prevent “travelling” of the contact heat zone, which can be caused by contact tolerance problems.

In particular, in the fine silicon rod 2 having a rectangular cross-sectional area, contact along the corner of the fine silicon rod is avoided.
As a result, a substantially large current can be passed, a higher temperature of the fine silicon rods 2 and 3 can be achieved, and rapid heating can be promoted. In addition, because graphite has a small diameter, i.e., the contact surface formed is narrow, the material becomes hot and a stronger mechanical and elastic bond between graphite and silicon occurs.

The contact-type clamping device according to the present invention can be suitably used in a vapor deposition reactor when silane vapor and water vapor are already introduced at the same time when the heating process of the thin silicon rods 2 and 3 is started.
This is possible because the contact surface between the rod holder 1 and the thin silicon rods 2 and 3 is already at a high temperature at the start of the heating process, and the introduced silane vapor or gas is deposited in a higher temperature region, This results in self-healing of the fine silicon rods 2 and 3. This results in improved stability.

  FIG. 7 is a plan view of a rod holder 16 for a circular thin silicon rod 13 which is another modified example, and FIG. 8 is a cross-sectional view of the rod holder 16 taken along line VIII-VIII in FIG. Is omitted. The fine silicon rod 16 is for the circular fine silicon rod 13 and is inserted in the same manner as described above.

  As clearly shown in FIG. 8, the rod holder 16 comprises a base element 17 and a clamping element 18 corresponding to the elements described above. The base element 17 has a cylindrical shape and is provided with conical recesses 20 at the lower part and the upper part. This recess is mirror-symmetric with respect to the center plane of the base element, so that the base element 17 is essentially in the shape of an H in its cross section. The base element 17 is rotationally symmetric with respect to the longitudinal axis A of the rod holder 16.

  The lower recess 20 is used to receive the contact element on the reactor side, whereby the base element 17 is received in the reactor and this causes electrical contact of the base element. Corresponding support and electrical connections can also be realized in the reactor by other methods, so that the lower recess 20 can be omitted. The upper recess 20 is used to receive the clamping element 18, as will be described below.

  The clamp element 18 includes three separate contact elements 25 and is connected to each other via a connecting land portion 26. As is apparent from the plan view of FIG. 7, the contact elements 25 are arranged at equal angular intervals through the connecting land portions 26, and extend radially toward a common center.

  A radially inwardly facing surface (inner surface) 28 of the contact element 25 forms a support space 30 for the fine silicon rod between the surfaces. As is apparent from FIG. 7, the inner surface 28 of the contact element 25 corresponds to the curvature of the fine silicon rod. The inner surface 28 is straight in the direction of the central longitudinal axis A of the rod holder 16 and extends parallel to the central longitudinal axis A.

  As can be seen in FIG. 7, the side surface 32 of the contact element 25 is oriented at an acute angle such that the width of the contact element 25 increases along the radial direction. However, the side faces are parallel to the direction of the central longitudinal axis A of the clamping element 16. Accordingly, the radially outward surface (outer surface) 34 of the contact element 25 is wider than the inner surface 28.

  As shown in the plan view of FIG. 7, the outer surface 34 has a curvature matched to the recess 20. Furthermore, the outer surface 34 is oriented at an acute angle relative to the inner surface 28 such that the contact element 25 tapers toward the bottom, as shown in FIG. The outer surface 34 has an inclination corresponding to the inclination of the tapered portion of the recess 20. One skilled in the art will recognize that when the clamping element 18 is pushed toward the recess 20, the contact elements 25 are pushed toward each other in the direction of the central longitudinal axis A.

  The connection land portion 26 extends between adjacent contact elements 25, and there is one connection land portion in each of the upper region and the lower region of the contact element 25. The connecting land portion is provided to hold the contact elements in a predetermined angular relationship with each other. When the contact elements 25 move so as to approach each other, the connecting land portion is deformed and, if necessary, cut at a predetermined cutting point. In this manner, the connecting land portion mainly serves the purpose of maintaining the contact elements 25 in a predetermined positional relationship with each other before the contact elements 25 are inserted into the base body 17. This positional relationship changes upon insertion, but this is achieved by the flexibility of the connecting land portion or by breaking the connecting land portion, ie, cutting at a predetermined cutting point. The contact element 25 and the connecting land portion 26 may be formed separately or integrally with the same material or with different materials.

  In the drawing, the connecting land portion 26 is provided between the side surfaces 32 of the contact element 25. However, when the contact element 25 is inserted into the recess 20, relative movement between the contact elements 25 is possible. It should be understood that other connections may be provided that can hold the contact elements 25 in a predetermined positional relationship with each other. In this way, for example a star-shaped coupling element is provided which extends between the inner surfaces 28 of the contact elements 25 and at the same time serves as the lower boundary of the support space 30 between the contact elements 25. It is also possible not to provide any connection between the contact elements 25. In order to simplify the handling of the contact elements 25, a guide for the contact elements 25 may be provided, for example, in the recess 20 of the base element 17, especially when they are not connected to one another. These guides are provided in a predetermined angular relationship so that a single contact element can be received and guided.

  Furthermore, in the embodiment of FIGS. 7 and 8, four contact elements may be provided for three or more contact elements 25, for example thin silicon rods having a rectangular cross-sectional area. In this case, the inner surface 28 of the contact element 25 is formed in a flat shape without being curved. In general, it should be understood that the inner surface 28 of the contact element functioning as the contact surface coincides with the contact surface of the fine silicon rod. The contact element 25 and the base element 17 include at least a contact element usually made of graphite, and are formed of a conductive material.

  As mentioned above, although the preferable Example of this invention was explained in full detail, this invention is not limited to these Examples. In particular, combinations and exchanges of elements of different embodiments are also included. For example, the embodiment shown in FIGS. 7 and 8 can be used in combination with the clamp ring 9.

Claims (17)

A contact-type clamping device for incorporating a fine silicon rod into an electrical contact with the silicon rod in a silicon vapor deposition reactor, comprising a rod holder (1; 6 ; 16) for supporting one end of the fine silicon rod. In
Said rod holder (1; 6; 16) comprises at least three contact elements (4; 5; 25) arranged around a support space (30) supporting a thin silicon rod (2; 3; 13). , Each contact element forms a contact surface (28) facing in the direction of the support space so as to contact the thin silicon rod (2; 3; 13) electromechanically, and adjacent contact elements (4; 5) ; 25 the contact surface of the) (28) contact clamping apparatus characterized by being spaced.   The contact-type clamping device according to claim 1, characterized in that the contact surface (28) extends parallel to the longitudinal axis (A) of the rod holder (1; 6; 16).   The contact-type clamping device according to claim 1 or 2, wherein the contact surface (28) has a stripe shape. Contact elements (4; 5; 25) is movable together, contact clamping device according to any one of claims 1 to 3, characterized in that it is movable in supporting lifting space (30) side . The contact surface (28) of the contact element (4; 5; 25) conforms to the shape of the fine silicon rod (2; 3 ; 13) so as to contact the fine silicon rod over a predetermined area. The contact-type clamping device according to any one of claims 1 to 4.   The rod holder (1; 6; 16) comprises at least two elements consisting of at least one base element (7; 17) and at least one clamping element (8; 18) with contact elements (4; 5; 25) The contact-type clamping device according to claim 1, comprising: Base element (17) is tapered pedestal that tapers in a circular cone shape made (20), the clamping element (18) is characterized in that it has a tapered outer shape corresponding to the cradle claims Item 7. A contact-type clamping device according to Item 6.   The taper of the cradle (20) of the base element (17) and the taper profile of the clamp element (18) are such that when the clamp element (18) moves toward the cradle (20), the contact element (25) comes together. 8. Contact-type clamping device according to claim 7, characterized in that it is dimensioned to move and to narrow the support space (30).   9. Contact-type clamping device according to claim 4 or 8, characterized in that the contact element (5; 25) moves perpendicular to the contact surface (28) of the contact element.   10. The contact-type clamping device according to claim 1, wherein the contact elements (4; 5; 25) are arranged at equal intervals around the support space (30).   11. The contact-type clamping device according to claim 1, wherein the contact elements (25) are separate elements connected to each other by a connecting element (26) at least before use.   The connecting element (26) between the contact elements is flexible and / or has a predetermined cut point so that it can be moved relatively between each contact element (25). The contact-type clamping device according to claim 11.   The contact-type clamping device according to claim 11 or 12, wherein the contact element (25) and the connecting element (26) are integrally formed. A clamping ring (9) fixed to the base element (7), the cradle receiving the contact element (5) being formed between the clamping ring (9) and the base element (7), the cradle being a clamping ring (9) when attached to the base element (7), claim it, characterized in being dimensioned such that they can contact element (5) moves moves the supporting lifting space sides 5 Or the contact type clamping apparatus of 13.   15. Contact-type clamping device according to claim 14, characterized in that the clamp ring (9) is attached to the base element (7) by screwing or is fastened to the base element (7) by a quick-release mechanism. .   16. Contact type according to claim 14 or 15, characterized in that the clamping ring (9) has an opening (10) with a tapered inner wall that matches the tapered outer shape of the contact element (5). Clamping device. The contact element (4; 5; 25) is fitted and / or closely fitted via a contact surface (28) with the fine silicon rod (2; 3; 13) received in the rod holder (1; 6; 16). The contact-type clamping device according to any one of claims 1 to 16, wherein the contact-type clamping device is in pressure contact.

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